Self-cureable and low temperature cureable polyesters

Abstract

Polyesters having both α,β-unsaturated groups and moieties containing activated methylene or methine groups, such as those of beta-ketoacetate and malonate, are curable in the presence of a base catalysts to form crosslinked networks. Formulations based on such polyesters are suitable for use in coatings and adhesive applications, and have the characteristics of curing at temperatures less than 230° C. without the use of isocyanates.

We claim: 
     
         1 . A composition comprising:
 A. a polyester comprising the residues of
 I. a first compound comprising an α,β-unsaturated carboxyl compound having at least one carboxylic acid or anhydride group having at least one unsaturation in the position that is α,β relative to said carboxylic acid or anhydride group and not located on an aromatic ring; and 
 II. a second compound having an activated methylene or methine group; and 
   B. a basic catalyst.   
     
     
         2 . The composition of  claim 1  wherein said second compound is selected from the group consisting of diketene, β-ketotoacetate, and malonate and mixtures thereof. 
     
     
         3 . The composition of  claim 1 , wherein said first compound is selected from the group comprising maleic anhydride, maleic acid, fumaric acid, itaconic acid, itaconic anhydride and mixtures thereof. 
     
     
         4 . The composition of  claim 1 , wherein said second compound is one or more selected from the group comprising diketene, t-butyl acetoacetate, methyl acetoacetate, ethyl acetoacetate, n-propyl acetoacetate, isopropyl acetoacetate, n-butyl acetoacetate, malonic acid, dimethyl malonate, diethyl malonate and mixtures thereof. 
     
     
         5 . A composition comprising:
 A. an acetoacetate-functionalized unsaturated polyester comprising the reaction product of:
 I. an unsaturated polyester in an amount from about 50 to about 97 weight percent, based on the total weight of (I) and (II), comprising the residues of:
 a. a hydroxyl component comprising:
 i. a diol in an amount ranging from 70 to 100 mole percent, based on the total moles of (i) and (ii), and 
 ii. a polyol in an amount ranging from 0 to 30 mole percent, based on the total moles of (i) and (ii), 
 
 b. an α,β-unsaturated carboxyl compound, and 
 c. optionally a carboxyl component other than said α,β-unsaturated carboxyl compound (b), comprising a polycarboxylic acid compound, a derivative of polycarboxylic acid compound, or a combination thereof, and 
 
 II. an alkyl acetoacetate and/or diketene in an amount ranging from about 3 to about 50 weight percent, based on the total weight of (I) and (II); and 
   B. a basic catalyst.   
     
     
         6 . The composition of  claim 5 , wherein said α,β-unsaturated carboxyl compound (b) is in an amount of 35 to 70 mole percent based on the total moles of the carboxyl components, (b) and (c). 
     
     
         7 . The composition of  claim 5 , wherein said unsaturated polyester (I) is in an amount of 70 to 90 weight percent and said alkyl acetoacetate and/or diketene (II) is in an amount of 10 to 30 weight percent, all based on the total weight of (I) and (II). 
     
     
         8 . The composition of  claim 5 , wherein said alkyl acetoacetate (II) is t-butyl acetoacetate. 
     
     
         9 . A composition comprising:
 A. a polyester comprising the residues of:
 a. a hydroxyl component comprising:
 i. a diol in an amount ranging from 70 to 100 mole percent, based on the total moles of (i) and (ii), and 
 ii. a polyol in an amount ranging from 0 to 30 mole percent, based on the total moles of (i) and (ii), 
 
 b. an α,β-unsaturated carboxyl compound, 
 c. malonic acid, its ester, or a combination thereof, and 
 d. optionally a carboxyl component other than said α,β-unsaturated carboxyl compound (b) and other than said malonic acid and/or its ester (c), comprising a polycarboxylic acid compound, a derivative of polycarboxylic acid compound, or a combination thereof; and 
   B. a basic catalyst.   
     
     
         10 . The composition of  claim 9 , wherein said malonic acid and/or its ester (c) is in an amount of 20 to 60 mole percent based on the total moles of the carboxyl components, (b), (c), and (d). 
     
     
         11 . The composition of  claim 9 , wherein the α,β-unsaturated carboxyl compound (b) is in an amount of 35 to 70 mole percent based on the total moles of (b), (c), and (d). 
     
     
         12 . The composition of  claim 9 , wherein the α,β-unsaturated carboxyl compound (b) is in an amount of 30 to 50 mole percent, malonic acid (c) is in an amount of 30 to 50 mole percent, and the carboxyl compound (d) is in an amount of 0 to 40 mole percent, based on the total moles of the carboxyl components, (b), (c), and (d). 
     
     
         13 . The composition of  claim 1 , wherein the basic catalyst (B) is one or more selected from the group comprising 1,8-diazabicyclo-[5.4.0]undec-7-ene (DBU), 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (MTBD), 1,1,3,3-tetramethylguanidine (TMG), 1,4-diazabicyclo[2.2.2]octane (DABCO), triethylamine, N,N-dimethylethanolamine, ammonium hydroxide, triphenyl phosphine, and tributyl phosphine. 
     
     
         14 . The composition of  claim 1 , wherein the basic catalyst (B) is one or more selected from the group consisting of 1,8-diazabicyclo-[5.4.0]undec-7-ene (DBU), 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (MTBD), and 1,1,3,3-tetramethylguanidine (TMG). 
     
     
         15 . The composition of  claim 1 , wherein the basic catalyst (B) is in amount ranging from 0.5 to 5 weight percent based on the weight of the self-curable polyester (A). 
     
     
         16 . The composition of  claim 1  further comprising one or more organic solvents. 
     
     
         17 . The composition of  claim 16  wherein said organic solvents are selected from the group comprising xylene, methyl amyl ketone, methyl ethyl ketone, 2-butoxyethanol, ethyl-3-ethoxypropionate, toluene, propanol, butanol, cyclopentanone, cyclohexanone, ethyl acetate, and butyl acetate. 
     
     
         18 . A composition comprising:
 A. a polyester comprising the residues of
 I. a first compound having an α,β-unsaturated group; and 
 II. a second compound having an activated methylene or methine group; 
   wherein said first compound is an α,β-unsaturated carboxyl compound having at least one carboxylic acid or anhydride group, and having at least one unsaturation in the position that is α,β relative to said carboxylic acid or anhydride group and not located on an aromatic ring; and   wherein said second compound is one or more compounds selected from the group consisting of diketene, β-ketotoacetate, and malonate;   B. an amino crosslinker; and   C. an acid catalyst.   
     
     
         19 . The composition of  claim 18 , wherein said amino crosslinker is present in an amount of from about 10 to about 30 weight percent, based on the total weight of (A) and (B). 
     
     
         20 . The composition of  claim 18  wherein said amino crosslinker is hexamethoxymethylmelamine, tetramethoxymethylbenzoguanamine, tetramethoxymethyl urea, mixed butoxy/methoxy substituted methylmelamines, or a mixture thereof. 
     
     
         21 . The composition of  claim 18  wherein said acid catalyst is p-toluenesulfonic acid, dinonylnaphthalene disulfonic acid, dodecylbenzenesulfonic acid, phosphoric acid, or mixtures thereof.